[yt-dev] advice on derived field debugging

[Britton Smith]

Hi all,

Kacper and Matt were correct.  The nuclei density fields were getting
created before their dependencies.  The issue was that the
add_nuclei_density_fields call needed to be moved into the species fields
plugin.  I've issued a PR to fix this.  Thanks for your help.

Britton

On Thu, Oct 2, 2014 at 2:42 PM, Kacper Kowalik <xarthisius.kk at gmail.com>
wrote:

> On Thu, Oct 2, 2014 at 12:37 PM, Britton Smith <brittonsmith at gmail.com>
> wrote:
>
>> Hi Kacper, Matt,
>>
>> Yes, that fixes the problem, although I am rather confused as to why.
>> The nuclei density fields depend on the species fields, so I would have
>> thought that the species fields need to be added first.  Can someone
>> explain what is happening here?
>>
>
> If species list is empty (calling add_nuclei_dens... will do that),
> there's a fallback that adds ["H", "He"] at
>  yt/fields/species_fields.py:123.
> I should be clear that what I've suggested was merly a workaround.
>
> Cheers,
> Kacper
>
>
>> Britton
>>
>> On Thu, Oct 2, 2014 at 9:10 AM, Kacper Kowalik <xarthisius.kk at gmail.com>
>> wrote:
>>
>>> On Thu, Oct 2, 2014 at 9:03 AM, Matthew Turk <matthewturk at gmail.com>
>>> wrote:
>>>
>>>> Hi Britton,
>>>>
>>>> On Thu, Oct 2, 2014 at 8:34 AM, Britton Smith <brittonsmith at gmail.com>
>>>> wrote:
>>>> > Hi all,
>>>> >
>>>> > There seems to be an issue accessing the nuclei density fields.
>>>> These are
>>>> > derived fields that give the total number density of an element with
>>>> names
>>>> > like "H_nuclei_density."  At some point, these have stopped working
>>>> and I am
>>>> > trying to debug this.  To reproduce this, one can do the following:
>>>> > ds = yt.load("enzo_cosmology_plus/DD0046/DD0046")
>>>> > ad = ds.all_data()
>>>> > ad["H_nuclei_density"]
>>>> >
>>>> > I have traced this as far as the following.  In the call to
>>>> > create_field_info, a YTFieldNotFound exception is raised on line 137
>>>> of
>>>> > yt/fields/species_fields.py.  Here, the nuclei density field function
>>>> is
>>>> > trying to access a number density field that should exist, but
>>>> doesn't seem
>>>> > to at the moment.  Later on it does, but not at this moment.  Does
>>>> anyone
>>>> > have any advice for where to look next?
>>>>
>>>> It might have to do with the order of field addition.  When does the
>>>> field actually get added?  Can you insert pdb calls into add_field
>>>> whenever the field you're looking for is added, and see when it occurs
>>>> compared to when the other one does?
>>>>
>>>
>>> Hi Britton,
>>> it's just as Matt suggested. Creating nuclei fields prior to species
>>> fields fixes the issue:
>>>
>>> http://paste.yt-project.org/show/5143/
>>>
>>> Cheers,
>>> Kacper
>>>
>>> _______________________________________________
>>> yt-dev mailing list
>>> yt-dev at lists.spacepope.org
>>> http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org
>>>
>>>
>>
>> _______________________________________________
>> yt-dev mailing list
>> yt-dev at lists.spacepope.org
>> http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org
>>
>>
>
> _______________________________________________
> yt-dev mailing list
> yt-dev at lists.spacepope.org
> http://lists.spacepope.org/listinfo.cgi/yt-dev-spacepope.org
>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.spacepope.org/pipermail/yt-dev-spacepope.org/attachments/20141006/b601d2ab/attachment.html>